Ok, I think I have scizophrenia, but I am not sure, I would like some advice from the community.

I don't really know when it started, but I had many of these symptoms when I was 12+ but the worse of them started half a year ago, I tried to shake this off, but it just gets worse.

I am agitated all the time, it takes my half an hour to get to sleep, and I tend to randomly spasm my muscles in agitation. Whenever I am in public, I always turn my head and look to see if anyone is watching me, and I am always on a constant state of alert. I have curtains installed in my house in all places, and plan on getting blacked out windows all over. I have never really 'connected' with anybody, and only had one friend throughout my life, and we had dropped out of contact years ago because we were competitive. I've had trouble in school/collage throughout my life, and I have had poor grades as a result. I tend to talk to myself, and after hearing my recordings, these talking sessions last at least half an hour to three hours. I also burst out laughing randomly by myself, and I always imagine myself to be a big-shot, and always have fantasies of being a billionaire/hot shot. Or other times, I believe I'm a savior, and relive these fantasies daily for hours in my head/aloud. Regarding social behavoir, I always 'sit in the back', and ever since I was young, was socially awkard and never really had any friends or personal connections with anybody. 

Whenever I talk to people, they often don't understand me, either I go off tangents, or they just don't get it. It takes me several tries to say anything, and I often repeat words randomly in sentences. I am scared most of the time, and aggressive, and don't talk. Whenever I go out in public, I try and get done whatever I have to do, and get back in a closed space as soon as possible. 

People I talk to(@ the workplace), feel I have no emotions/brutish. My personality is very rational, and I brush off emotions easily. When I was young, and still now, I am shunned, people think I'm weird and lack emotion. Also I am 'loud-mouthed'.

The more serious symptoms have started in the past six months.

I started having re-occurring nightmares, and whenever I 'drift' off to sleep I hear voices saying 'I shouldn't exist' or 'get out/go' or 'it's all going to end'. I try to repress them, and drift off into nightmares, when they taunt me relentlessly.

Also, now I am hearing voices during the day time, and once I saw a ghost image of myself, talking to me and I was making casual conversation with myself (with this projected hallucination of me), but then after a few minutes, I realized what I was doing, and immidiatly stopped. My hallucination then threatened me and vowed to come back. He does so, hating me.

Now to deal with this, I press knuckles against my temples, until the pain blocks out the voices/emotions/stress. I get dizzy afterwards, but the 'scizophrenia' stops temporaily. I now understand why people cut them self, but I don't want to as it leaves physical alterations.

*I also get massive headaches. No longer than one minute, but a good 8 or nine on pain scale.

Also, my brother is autistic, does this increase the risk of schizophrenia genetically?

Is this scizophrenia, I suspect it is, but I need a neutral authority to verify my conclusion.

Thank you for your time to help.

HealsKitPro13